Home made gravy/sauce is so simple made from a fast rue I can't imagine buying a mix or using canned. The only thing I do use from a jar is rye bread caramel. It makes the grave deep brown when I want dark gravy. Adds no taste to it just a deep brown color.
Boil egg noodles to just about done. Add small amount of heavy cream to hot drained pasta with butter in the hot pot. Heat and stir until milk liquid has evaporated. Noodles will be coated. Add salt and pepper.
Cover noodles with roast beef in dark gravy or light gravy. Light gravy being made with sour cream or cream cheese added to the rue gravy. I always use chicken or beef stock to liquify the rue.